Yes there's a nip for that 😉
Alby extension https://guides.getalby.com/user-guide/v/alby-account-and-browser-extension/alby-browser-extension/features/master-key
BorderWallets https://mtc.substack.com/p/how-to-create-a-memorable-nostr-private
Discussion
But sadly it needs to be done first, cannot create a seed phrase for existing npub
I see. I guess when you consider how new nostr is, its probably similar to early Bitcoin and things just aren't built out yet.
so to get a seed phrase for my private key I would need to create a new profile? hmm.
Sometimes it feels like trying to drive a car while there's mechanics still fitting things like seatbelts and window winders!